1. Field of the Invention
The present invention relates generally to a capstan shaft cleaning device.
2. Description of the Related Art
Generally, an apparatus for magnetically recording and reproducing information such as, for example, a digital audio tape recorder, or DAT, is provided with a capstan shaft and pinch roller for making a magnetic recording medium such as a magnetic tape run at a constant speed. The capstan shaft is rotated at a constant rpm by a capstan motor, the pinch roller presses the magnetic tape against the capstan shaft during a tape loading operation and the tape runs at a constant speed corresponding to the rotation of the capstan shaft, making it possible to carry out stable magnetic recording and reproduction of information to and from the magnetic tape.
As described above, the capstan shaft is in sliding contact with the magnetic tape during magnetic recording and reproduction, so magnetic particles can come loose from and fall off the magnetic tape onto the capstan shaft. Once these magnetic particles fall onto the capstan shaft the magnetic tape can no longer run with stability.
As a result, the conventional magnetic recording/reproduction apparatus is provided with a cleaning device to remove magnetic particles and other such dirt and dust from the capstan shaft.
FIG. 1 is a partial cutaway plan view of a conventional capstan shaft cleaning device. As shown in the diagram, the capstan shaft 2 is supported so as to rotate freely within a capstan housing 3.
A felt material 4 that functions as a cleaning device 1 is affixed to the capstan housing 3. The felt material 4 is positioned so as to contact the capstan shaft 2 from a side opposite the side on which the magnetic tape slidingly contacts the capstan shaft 2. Accordingly, the felt material 4 is in continuous contact with the capstan shaft 2, wiping away magnetic particles and other dirt.
However, a problem arises in that although the conventional cleaning device 1 using a felt material 4 performs adequately at first, over time the felt material 4 becomes dirty and its effectiveness as a cleaner diminishes sharply. In the worst case, magnetic particles adhering to the felt material 4 come off onto the capstan shaft 2.
Additionally, because the felt material 4 is affixed to the capstan housing 3 it is not easy to replace the felt material 4 when the felt material 4 becomes dirty. Moreover, because the felt material 4 is used under high-temperature conditions the felt material 4 sometimes peels off from the capstan housing 3.
Accordingly, it is a general object of the present invention to provide an improved and useful capstan shaft cleaning device in which the disadvantages described above are eliminated.
A further object of the present invention is to provide an improved and useful capstan shaft cleaning device in which the cleaning effectiveness thereof can be maintained for an extended period of time.
The above-described objects of the present invention are achieved by a capstan shaft cleaning device comprising:
a cleaning member removing dirt attached to a capstan shaft; and
a moving mechanism moving the cleaning member between a position at which the cleaning member contacts the capstan shaft and a position at which the cleaning member is separated from the capstan shaft,
the cleaning member having at least two points of contact contacting a periphery of the capstan shaft.
According to the invention described above, the effectiveness of the capstan shaft cleaning device can be maintained over an extended period of time. In particular, because cleaning member contact points are formed at at least two points along a peripheral direction of the capstan shaft, the capstan shaft cleaning device can still securely slidably contact the capstan shaft and remove magnetic particles and other dirt adhering to the capstan shaft even if the assembled capstan shaft cleaning device and the capstan shaft are out slightly of position with respect to each other.
Additionally, the above-described objects of the present invention are also achieved by the capstan shaft cleaning device as described above, wherein:
the contact points of the cleaning member are made of a hard resin material including an antistatic agent; and
the contact points form projections with obtuse angles in cross-section in a direction of a radius of the capstan shaft.
According to the invention described above, there is no diminution in cleaning power as is the case with the conventional felt material and cleaning effectiveness can be maintained over an extended period of time.
Additionally, the above-described objects of the present invention are also achieved by a capstan shaft cleaning device comprising:
a cleaning member removing dirt attached to a capstan shaft; and
a moving mechanism moving the cleaning member between a position at which the cleaning member contacts the capstan shaft and a position at which the cleaning member is separated from the capstan shaft,
the moving mechanism being provided with a follow mechanism that displaces so that a contact line of the cleaning member contacting the capstan shaft adheres closely to the capstan shaft.
Additionally, the above-described objects of the present invention are also achieved by a capstan shaft cleaning device as described above, wherein the cleaning member comprises:
an arm; and
a bearing part,
a contact portion having a contact line parallel to an axis of the capstan shaft provided at one end of the arm, the bearing part extending cylindrically from an intermediate position of the arm in a direction parallel to the axis of the capstan shaft, the bearing part supported by a shaft, a gap being provided between the shaft and a portion of the bearing part parallel to a surface including the two contact lines of the cleaning member, a projection being formed at a portion of the bearing part near a side on which the arm is provided, the bearing part being engaged by the shaft via the projection as to be displaceable about the projection, the contact line of the cleaning member following and adhering closely to the capstan shaft.
According to the invention described above, the contact line of the cleaning member changes so as to follow and closely adhere to the capstan shaft and ensure removal of magnetic particles and other dirt adhering to the capstan shaft.
Other objects, features and advantages of the present invention will become more apparent from the following detailed description when read in conjunction with the accompanying drawings.